The present invention relates to a method for setting the desired closure travel between a closing body and its valve seat in a central valve arranged in a piston of a master cylinder, the closing body abutting, in the inoperative position, with an axial extension against a positive stop. A thusly designed master cylinder with central valve is described, for instance, in the German printed and published patent application DE-OS 36 27 000. The closure travel of the central valve of an aforementioned master cylinder has normally been set such that after the assembly of all internal parts of the master cylinder, a functional dimension is set between a flange at the cylinder housing and the point of application of force of the actuating member of the pedal and/or power booster by inserting spacer discs. Said setting method is disadvantageous in that when designing the closure travel of the central valve the tolerances of the functional dimension and of the preceding power booster must be taken into account since it must be ensured that the central valve is open in the inoperative position since otherwise a residual pressure can remain in the hydraulic circuit.